| Contadero Formation | |
| Type: | Formation |
| Period: | late Devonian |
| Prilithology: | Limestone, shale |
| Otherlithology: | Siltstone |
| Namedby: | F.V. Stevenson |
| Year Ts: | 1945 |
| Region: | New Mexico |
| Country: | United States |
| Coordinates: | 33.1927°N -106.6305°W |
| Subunits: | Salinas Peak Member, Thurgood Member, Rhodes Canyon Member.[2] |
| Underlies: | Lake Valley Formation |
| Overlies: | Sly Gap Formation |
The Contadero Formation is a geologic formation in the San Andres Mountains of New Mexico. It preserves fossils dating back to the late Devonian period.
The formation consists of limestone, shale, and siltstone. The total thickness is 66.5feet at the type section. It overlies the Sly Gap Formation and underlies the Lake Valley Limestone.
The formation is divided into three members (in ascending stratigraphic order): the Salinas Peak Member, the Thurgood Member, and the Rhodes Canyon Member.
The formation is thought to correlate with the lower Percha Shale.
The formation contains brachiopods and horn corals, with 20 genera and 24 species of brachiopods identified. These are characteristic of the late Frasnian.
The formation was first defined by Frank V. Stevenson in 1945 for exposures at Rhodes Canyon in the San Andres Mountains. While revising New Mexico Devonian stratigraphy in 1984, Souraf assigned all Devonian beds above the Sly Gap Formation to the Conadero Formation, including beds previously assigned to the Thoroughgood and Rhodes Canyon Formations, which were reduced to member rank within the Conadero Formation. Souraf also designed a new Salinas Peak Member and changed the spelling of Thoroughgood to Thurgood.